Surgical instruments of the type of this class have been known for a quite some time. They have different names for different intended uses. For example, bone punches, rongeurs as well as endoscopic punches can be mentioned here, and this listing shall not be considered to be limiting. It is common to these instruments that they have a gripping part with a kind of guide housing, in which a tool is mounted replaceably. This tool is activated by actuating an actuating lever, and this tool may be, for example, a punching tool, a gripping tool or even a kind of scissors.
Reference shall be made for this, for example, to DE 20 2008 006 005 U1. The subject of this German utility model is a so-called bone punch. Such a bone punch differs, for example, from an endoscopic punch by the concrete embodiment of the tool proper. A guide housing, which is rigidly in connection with a gripping part, is provided in the prior-art bone punch. This gripping part forms a rigid gripping element and has an actuating lever, which is pivotable in relation to the gripping part or gripping element. This actuating element forms a lever section, by which a plunger of the punching tool, which said plunger is mounted in the guide housing and is provided with a pushbutton, is adjustable axially during the actuation of the actuating lever. A punch slide, which can be adjusted by the plunger along a punching bar from a retracted starting position into an advanced end position against the spring force of an axial compression spring, is in connection with said plunger. This axial compression spring is arranged in the area of the plunger between the pushbutton and a mounting housing of the plunger, so that the plunger is held via the pushbutton thereof in its retracted starting position by this axial compression spring. Furthermore, the mounting housing is provided with a ring shoulder in its end area located in the guide housing. In the state in which the mounting housing is mounted in the guide housing, the mounting housing is held in the guide housing in an axially stationary manner via this ring shoulder and a locking element protruding into a guide hole of the guide housing, which said guide hole receives the mounting housing.
This locking element can be shifted from a locking position, which fixes the mounting housing and hence the entire punching tool and protrudes into the guide housing, into a pivoted position releasing the mounting housing or the ring shoulder thereof in the actuation direction. This surgical instrument, called a bone punch, has an extremely complicated design in the area of the gripping part because of this locking element. In particular, a plurality of processing steps are necessary in the area of the gripping part and hence in the area of the guide housing in order to make it possible to insert the locking element. Furthermore, this locking element must be held in its locked position by spring force, so that the mounting housing of the plunger remains stationarily in the guide housing of the gripping part. By actuating this locking element, the latter moves with its locking nose out of the guide hole of the guide housing, so that the entire punching tool with its mounting housing can be removed from the gripping part or the guide housing to the front. Furthermore, this construction has the risk in case of inexperienced handling that the locking element is accidentally actuated and the mounting housing and hence the punching tool proper will unintentionally slip out of the guide housing during use.
It shall be mentioned here once again that, for example, scissors or a gripper or the like may also be provided as the tool instead of the punching slide or the punching tool at the free end of the “punching bar.”